Many-Body Expansion Dynamics of a Bose-Fermi Mixture Confined in an Optical Lattice

We unravel the correlated non-equilibrium dynamics of a mass balanced Bose-Fermi mixture in a one-dimensional optical lattice upon quenching an imposed harmonic trap from strong to weak confinement. Regarding the system's ground state, the competition between the inter and intraspecies interaction strength gives rise to the immiscible and miscible phases characterized by negligible and complete overlap of the constituting atomic clouds respectively. The resulting dynamical response depends strongly on the initial phase and consists of an expansion of each cloud and an interwell tunneling dynamics. For varying quench amplitude and referring to a fixed phase a multitude of response regimes is unveiled, being richer within the immiscible phase, which are described by distinct expansion strengths and tunneling channels. During the bosonic (fermionic) expansion the predominantly occupied wells show a correlated (anti-correlated) behavior and are incoherent as well as two-body anti-correlated among each other. Finally, the dependence of the response strength on the potential barrier height and the mass ratio of the components is discussed.